In the past nine months or so, Verizon has used the tactic to retain thousands of subscribers in the Northeast and Mid-Atlantic, as well as in parts of the Midwest, South, Texas and California, according to the cable companies.

Verizon said that it is not doing anything illegal and that its marketing is good for consumers, USA Today reported.

The dispute stems from the fact that when a cable operator gains a customer from Verizon, the operator must contact Verizon to transfer the customer’s phone number since most customers wish to retain the same number.

These transfers can take several days, and during that time, the cable operators allege that Verizon is illegally using information about the transfer to encourage customers to stay with the telco by offering them service discounts and gift cards.

A Verizon executive said that the cable operators are trying to block consumer choice, USA Today reported.